1 /** \file
2 * Inkscape::GC::soft_ptr - "soft" pointers to avoid finalization cycles
3 *
4 * Copyright 2006 MenTaLguY <mental@rydia.net>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 *
11 * See the file COPYING for details.
12 *
13 */
15 #ifndef SEEN_INKSCAPE_GC_SOFT_PTR_H
16 #define SEEN_INKSCAPE_GC_SOFT_PTR_H
18 #include "gc-core.h"
20 namespace Inkscape {
22 namespace GC {
24 /** @brief A class for pointers which can be automatically cleared to break
25 * finalization cycles.
26 */
27 template <typename T>
28 class soft_ptr {
29 public:
30 soft_ptr(T * const &pointer=NULL) : _pointer(pointer) {
31 _register();
32 }
33 soft_ptr(soft_ptr const &other) : _pointer(other._pointer) {
34 _register();
35 }
37 operator T *() const { return _pointer; }
38 T &operator*() const { return *_pointer; }
39 T *operator->() const { return _pointer; }
40 T &operator[](int i) const { return _pointer[i]; }
42 soft_ptr &operator=(T * const &pointer) {
43 _pointer = pointer;
44 return *this;
45 }
47 // default copy
49 private:
50 void _register() {
51 void *base=Core::base(this);
52 if (base) {
53 Core::general_register_disappearing_link((void **)&_pointer, base);
54 }
55 }
57 T *_pointer;
58 };
60 }
62 }
64 #endif
65 /*
66 Local Variables:
67 mode:c++
68 c-file-style:"stroustrup"
69 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
70 indent-tabs-mode:nil
71 fill-column:99
72 End:
73 */
74 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :